Question

what is the energy associated in joules with a photon of wavelength 4000​

Answer 1

$\huge\mathcal{Answer:}$

$4.97 \times 10 {}^{ - 9} joule$

$e = \frac{hc}{λ}$

$= \frac{6.626 \times 10 {}^{ - 34} }{4000 \times 10 {}^{ - 10}m } js \times 3 \times 10 {}^{8} m/s$

$e = 4.97 \times 10 {}^{ - 19} joule$